Medical signal processing device and medical observation system

ABSTRACT

A medical signal processing device processes an image signal received in accordance with a result of examining inside of a subject. The image signal includes pixel data groups that are data of respective pixels different from each other and received by the medical signal processing device in parallel. The medical signal processing device includes a distribution processing unit configured to generate distributed image signals by distributing the pixel data groups, and the distribution processing unit distributes the pixel data groups such that, among the pixel data groups, pieces of data at bit positions of most significant digits of the pixel data groups of pixels adjacent to each other are included in the respective distributed image signals different from each other. The distributed image signals are transmitted to an external medical control device through respective signal transmission paths.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to and incorporates by referencethe entire contents of Japanese Patent Application No. 2016-006644 filedin Japan on Jan. 15, 2016.

BACKGROUND

The present disclosure relates to a medical signal processing device.

Medical observation systems in the medical field are configured tocapture an image of the inside of a subject such as a human (inside of aliving body) to observe the inside of this living body (for example,refer to Japanese Patent Laid-open No. 2009-61032 and Japanese PatentLaid-open No. 2006-26134).

Medical observation systems disclosed in Japanese Patent Laid-open No.2009-61032 and Japanese Patent Laid-open No. 2006-26134 (“electronicendoscope systems” in Japanese Patent Laid-open No. 2009-61032 andJapanese Patent Laid-open No. 2006-26134) each include a medicalobservation device (“electronic endoscope” in Japanese Patent Laid-openNo. 2009-61032 and Japanese Patent Laid-open No. 2006-26134) configuredto capture an image of the inside of a living body and output an imagesignal, a control device (“video processor” in Japanese Patent Laid-openNo. 2009-61032 and “processor” in Japanese Patent Laid-open No.2006-26134) configured to receive the image signal from the medicalobservation device and process the image signal to generate a displayimage signal, and a signal transmission path (“wireless connector” inJapanese Patent Laid-open No. 2009-61032 and “signal line” in JapanesePatent Laid-open No. 2006-26134) through which the image signal from themedical observation device is transmitted to the control device.

SUMMARY

When a failure occurs in transmission of the image signal due to, forexample, breaking of the signal transmission path, the control device isunable to appropriately generate the display image signal and display animage suitable for observation.

In the medical observation system disclosed in Japanese Patent Laid-openNo. 2009-61032, when a signal transmission state in the signaltransmission path is detected and the detected transmission state isinappropriate for transmission, an operator is warned or notified by,for example, a buzzer. However, in the medical observation systemdisclosed in Japanese Patent Laid-open No. 2009-61032, an image suitablefor observation may not be displayed until the signal transmission pathis replaced by, for example, the operator in response to this warning ornotification.

The medical observation system disclosed in Japanese Patent Laid-openNo. 2006-26134 is provided with at least two signal transmission pathsthrough which an identical image signal is transmitted. With thisconfiguration, in the medical observation system disclosed in JapanesePatent Laid-open No. 2006-26134, when a transmission failure occurs inone of the signal transmission paths, the image signal may betransmitted to the control device through the other signal transmissionpath, which achieves continuous display of an image suitable forobservation. However, one of the signal transmission paths isunnecessary when no transmission failure occurs. In other words, in themedical observation system disclosed in Japanese Patent Laid-open No.2006-26134, the above-described signal transmission path needs to beredundantly provided, which prevents simplification of the structure.

It has been desired to achieve a technique of performing, with asimplified structure, continuous display of an image suitable forobservation when a transmission failure occurs in a signal transmissionpath.

There is a need for a medical signal processing device and a medicalobservation system capable of performing, with a simplified structure,continuous display of an image suitable for observation when atransmission failure occurs in a signal transmission path.

A medical signal processing device according to one aspect of thepresent disclosure receives an image signal in accordance with a resultof examining inside of a subject and processes the image signal. Theimage signal includes a plurality of pixel data groups of respectivepixels arrayed at a constant interval among pixels sequentially arrayedin a predetermined direction in an image made of pixels arrayed in amatrix, the pixel data groups are data of respective pixels differentfrom each other, the pixel data groups are received by the medicalsignal processing device in parallel, the medical signal processingdevice includes a distribution processing unit configured to generate aplurality of distributed image signals by distributing the pixel datagroups, the distribution processing unit distributes the pixel datagroups such that, among the pixel data groups, pieces of data at bitpositions of most significant digits of the pixel data groups of pixelsadjacent to each other are included in the respective distributed imagesignals different from each other, and the distributed image signals aretransmitted to an external medical control device through a plurality ofrespective signal transmission paths.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a schematic configuration of a medicalobservation system according to a first embodiment of the presentdisclosure;

FIG. 2 is a block diagram of the configurations of a camera head and acontrol device illustrated in FIG. 1;

FIG. 3A is a diagram illustrating an image signal output from an imagingunit illustrated in FIG. 2;

FIG. 3B is a diagram illustrating the image signal output from theimaging unit illustrated in FIG. 2;

FIG. 4 is a block diagram of the configuration of a transmission signalprocessing unit illustrated in FIG. 2;

FIG. 5 is a diagram illustrating first to tenth image signals after S/Pconversion processing is executed at an S/P conversion unit illustratedin FIG. 4;

FIG. 6 is a diagram illustrating first to fourth distributed imagesignals generated at a distribution processing unit illustrated in FIG.4;

FIG. 7 is a block diagram of the configuration of a received signalprocessing unit illustrated in FIG. 2;

FIG. 8A is a diagram illustrating an effect of the first embodiment ofthe present disclosure;

FIG. 8B is a diagram illustrating the effect of the first embodiment ofthe present disclosure;

FIG. 9 is a diagram illustrating the effect of the first embodiment ofthe present disclosure;

FIG. 10 is a diagram illustrating a schematic configuration of a medicalobservation system according to a second embodiment of the presentdisclosure; and

FIG. 11 is a diagram illustrating a schematic configuration of a medicalobservation system according to a third embodiment of the presentdisclosure.

DETAILED DESCRIPTION

Configurations to achieve the present disclosure (hereinafter referredto as embodiments) will be described below with reference to theaccompanying drawings. The embodiments described below, however, are notintended to limit the present disclosure. In description of thedrawings, any identical parts are denoted by an identical referencenumeral.

First Embodiment

Schematic Configuration of Medical Observation System

FIG. 1 is a diagram illustrating a schematic configuration of a medicalobservation system 1 according to a first embodiment of the presentdisclosure.

The medical observation system 1 is used in the medical field to observethe inside of a subject such as a human (inside of a living body). Asillustrated in FIG. 1, the medical observation system 1 includes anendoscope 2, a light source device 3, a display device 4, a secondtransmission cable 5, a control device 6, a third transmission cable 7,and a light guide 8.

The endoscope 2 examines the inside of the living body and outputs animage signal (a plurality of transmission image signals) in accordancewith a result of this examination. As illustrated in FIG. 1, theendoscope 2 includes an insertion unit 21, a camera head 22, and a firsttransmission cable 23.

The insertion unit 21 is hard or at least partially soft, has anelongated shape, and is inserted into the inside of the living body. Theinsertion unit 21 includes an optical system that includes one or aplurality of lenses and through which an object image is condensed.

The light source device 3 is connected with one end of the light guide8, and supplies, under control of the control device 6, this one end ofthe light guide 8 with light for illumination of the inside of theliving body.

The light guide 8 has one end detachably connected with the light sourcedevice 3 and the other end detachably connected with the insertion unit21. The light guide 8 transfers the light supplied by the light sourcedevice 3 from the one end to the other end to supply the light to theinsertion unit 21. The light supplied to the insertion unit 21 isemitted from a leading end of the insertion unit 21 and incident on theinside of the living body. The light (object image) incident on theinside of the living body is condensed through the optical system in theinsertion unit 21.

The camera head 22 is detachably connected with a base end of theinsertion unit 21. The camera head 22 captures, under control of thecontrol device 6, the object image condensed through the insertion unit21 and generates an image capturing signal (image signal). The camerahead 22 also generates a plurality of transmission image signals fromthis image signal and outputs these transmission image signals. In thefirst embodiment, the camera head 22 converts these transmission imagesignals into optical signals and outputs these transmission imagesignals as the optical signals.

The configuration of the camera head 22 will described later in detail.

The first transmission cable 23 has one end detachably connected withthe control device 6 through a connector CN1 (FIG. 1) and the other endconnected with the camera head 22 through a connector CN2 (FIG. 1).Specifically, the first transmission cable 23 includes a plurality ofelectric wires 231 (refer to FIG. 2) and a plurality of optical fibers232 (refer to FIG. 2) arranged inside of an outer cover, which is anoutermost layer.

The electric wires 231 are electric wires for transmitting, for example,a control signal, a synchronizing signal, a clock, and electrical poweroutput from the control device 6 to the camera head 22. In FIG. 2, thenumber of the electric wires 231 is three but not limited thereto, andmay be any other number.

The optical fibers 232 are optical fibers for transmitting, to thecontrol device 6, the transmission image signals (optical signals)output from the camera head 22. In the first embodiment, the fouroptical fibers 232 of first to fourth optical fibers 2321 to 2324 (referto FIG. 2) are provided. The number of the provided optical fibers 232depends on the number of optical signals output from the camera head 22and is changed in accordance with any change in the number of opticalsignals.

The optical fibers 232 included in the first transmission cable 23 eachfunction as a signal transmission path according to the presentdisclosure.

The display device 4 includes a display exploiting, for example, liquidcrystal or organic electro luminescence (EL), and displays an imagebased on image signals processed at the control device 6.

The second transmission cable 5 has one end detachably connected withthe display device 4 and the other end detachably connected with thecontrol device 6. The second transmission cable 5 transmits imagesignals processed at the control device 6 to the display device 4.

The control device 6 includes, for example, a central processing unit(CPU) and performs overall control of operation of the light sourcedevice 3, the camera head 22, and the display device 4.

The configuration of the control device 6 will be described later indetail.

The third transmission cable 7 has one end detachably connected with thelight source device 3 and the other end detachably connected with thecontrol device 6. The third transmission cable 7 transmits, to the lightsource device 3, a control signal from the control device 6.

Configuration of Camera Head

The following describes the configuration of the camera head 22.

FIG. 2 is a block diagram of the configurations of the camera head 22and the control device 6.

For the purpose of description, FIG. 2 omits illustrations of theconnectors CN1 and CN2 connecting the control device 6 and the camerahead 22 with the first transmission cable 23, and connectors connectingthe control device 6 and the display device 4 with the secondtransmission cable 5.

As illustrated in FIG. 2, the camera head 22 includes a lens unit 221, adrive unit 222, an imaging unit 223, a transmission signal processingunit 224, and an electrical-optical conversion unit 225.

The lens unit 221 includes one or a plurality of lenses movable along anoptical axis and images the object image condensed through the insertionunit 21 onto an imaging plane of the imaging unit 223 (an image sensor2231 (refer to FIG. 3A)). The lens unit 221 is provided with an opticalzoom mechanism (not illustrated) that changes an angle of view by movingthe one or plurality of lenses, and a focus mechanism (not illustrated)that changes focus.

The drive unit 222 operates, under control of the control device 6, theoptical zoom mechanism and the focus mechanism described above to changethe angle of view and the focus of the lens unit 221.

The imaging unit 223 images the inside of the living body under controlof the control device 6. The imaging unit 223 includes a sensor chip onwhich, for example, the image sensor 2231 (refer to FIG. 3A), such as acharge-coupled device (CCD) or a complementary metal oxide semiconductor(CMOS), configured to receive the object image condensed through theinsertion unit 21 and imaged through the lens unit 221 and convert theobject image into an electric signal, and a signal processing unit (notillustrated) configured to perform signal processing (such as A/Dconversion) on the electric signal (analog signal) from the image sensor2231 to output an image signal are integrally formed, and outputs theimage signal (digital signal) after the A/D conversion. The signalprocessing unit (not illustrated) described above does not need to beformed integrally with the image sensor 2231 but may be formedseparately.

Further in the first embodiment, the imaging unit 223 outputs the imagesignal after the A/D conversion through 10 channels (first to tenthchannels CA to CJ (FIG. 2)) in parallel. The number of channels is notlimited to 10 but may be any other number.

The image signal from the imaging unit 223 according to the firstembodiment may be output as differential signals for the respectivechannels. In this case, for example, the signal processing unit (notillustrated) described above may be provided with a differentialconversion unit (not illustrated) configured to convert the image signalafter the A/D conversion into differential signals, and the transmissionsignal processing unit 224 to be described later may be provided with arestoring unit (not illustrated) configured to restore the differentialsignals to the original image signal.

FIGS. 3A and 3B are each a diagram illustrating the image signal outputfrom the imaging unit 223. Specifically, FIG. 3A is a diagramillustrating a physical arrangement of effective pixels of the imagesensor 2231. FIG. 3B is a diagram illustrating the image signal outputfrom the imaging unit 223.

The number of bits per pixel in the image signal output from the imagingunit 223 is 10 in the first embodiment, but may be any other number.

In FIG. 3A, pixels on the first row are denoted by sequential numbers(address numbers of “0”, “1”, “2”, . . . ) starting at the first column.Pixels at the second row are denoted by sequential address numbers(illustrated as, for example, a triangle in FIG. 3A) starting at thefirst column and following the address number of the pixel at the lastcolumn on the first row. The same notation applies to the third row andthe following rows. In FIG. 3A, each pixel is denoted by such an addressnumber followed by a reference sign (“CA” to “CJ”) in parentheses, ofany of the first to the tenth channels CA to CJ through which pixel datagenerated at this pixel is output. In addition, (a) to (j) in FIG. 3Billustrate pixel data (in FIG. 3B, for sake of simplicity, pixel data ofpixels at address numbers “0” to “9”) output through the first to thetenth channels CA to CJ. In FIG. 3B, an address number indicating apixel at which pixel data is obtained is provided at each bit positionof this pixel data, followed by this bit position (with a mostsignificant bit (MSB; the bit position of a most significant digit) of 9and a least significant bit (LSB; the bit position of a leastsignificant digit) of “0”in parentheses.

In the first embodiment, as illustrated in FIGS. 3A and 3B, the imagingunit 223 converts pixel data generated at the pixel of address number“0” into serial data, and outputs the serial data bit by bitsequentially from the MSB through the first channel CA. The imaging unit223 converts pixel data generated at the pixel of address number “1”into serial data, and outputs the serial data bit by bit sequentiallyfrom the MSB through the second channel CB. Similarly, the imaging unit223 converts each piece of pixel data generated at pixels of addressnumbers “2” to “9” into serial data, and outputs the serial data bit bybit sequentially from the MSB through the third to the tenth channels CCto CJ.

In the pieces of pixel data vertically arranged in FIG. 3B, pieces ofdata at an identical bit position are output simultaneously through thefirst to the tenth channels CA to CJ, respectively.

Specifically, the imaging unit 223 outputs, in parallel through thefirst to the tenth channels CA to CJ as described above, pieces of pixeldata (serial data) generated at 10 pixels each in an order of theaddress number.

In the first embodiment, as illustrated in FIG. 3A, pieces of pixel datagenerated at pixels at an identical column are output through anidentical channel.

Although not illustrated in FIGS. 3A and 3B, the imaging unit 223outputs timing reference codes “SAV1” to “SAV4” made of four words (oneword=10 bits) in parallel through the first to the tenth channels CA toCJ before outputting, in parallel through the first to the tenthchannels CA to CJ, pieces of pixel data (serial data) generated at 10pixels each in an order of the address number (refer to FIG. 5). Afteroutputting, in parallel through the first to the tenth channels CA toCJ, the pieces of pixel data (serial data) generated at 10 pixels eachin an order of the address number, the imaging unit 223 outputs timingreference codes “EAV1” to “EAV4” made of four words (one word=10 bits)in parallel through the first to the tenth channels CA to CJ (refer toFIG. 5).

Each image signal output in parallel through the first to the tenthchannels CA to CJ described above corresponds to a pixel data groupaccording to the present disclosure.

FIG. 4 is a block diagram of the configuration of the transmissionsignal processing unit 224.

In FIG. 4, the flow of a signal output in parallel data is illustratedby an arrow intersected with a diagonal line. The same notation appliesto FIG. 2 and the following figures.

The transmission signal processing unit 224 functions as a medicalsignal processing device according to the present disclosure andexecutes, on the image signal (in 10 bits through 10 channels) from theimaging unit 223, various kinds of processing such as S/P conversionprocessing, transmission image signal generation processing (mappingprocessing and auxiliary data addition processing), encoding processing(N bit/M (>N) bit conversion processing (in the first embodiment, 8bits/10 bits conversion processing)), and P/S conversion processing. Asillustrated in FIG. 4, the transmission signal processing unit 224includes an S/P conversion unit 226, a signal processing unit 227, and aplurality of drivers 228.

The S/P conversion unit 226 executes the S/P conversion processing onthe image signal (serial data in 10 bits through 10 channels) outputfrom the imaging unit 223 and converts the image signal into paralleldata.

FIG. 5 is a diagram illustrating first to tenth image signals FS1 toFS10 (parallel data) after the S/P conversion processing is executed atthe S/P conversion unit 226.

Numbers (“0” to “4249”) illustrated in FIG. 5 correspond to the addressnumbers illustrated in FIG. 3A and each indicate pixel data (10 bits)generated at a pixel of the corresponding address number. Pixel datagenerated at the pixels of address numbers “0” to “4249” is effectivedata (pixel data obtained in an effective image region).

Specifically, as illustrated in (a) in FIG. 5, the S/P conversion unit226 generates the first image signal FS1 (parallel data) by executingthe S/P conversion processing on an image signal (the timing referencecodes “SAV1” to “SAV4” and “EAV1” to “EAV4”, and pieces of pixel data(pieces of pixel data generated at the pixels of address numbers “0”,“10”, “20”, . . . )) output through the first channel CA. As illustratedin (b) in FIG. 5, the S/P conversion unit 226 also generates the secondimage signal FS2 (parallel data) by executing the S/P conversionprocessing on an image signal (the timing reference codes “SAV1” to“SAV4” and “EAV1” to “EAV4”, and pieces of pixel data (pieces of pixeldata generated at the pixels of address numbers “1”, “11”, “21”, . . .)) output through the second channel CB. Similarly, as illustrated in(c) to (j) in FIG. 5, the S/P conversion unit 226 generates the third tothe tenth image signals FS3 to FS10 (parallel data) by executing the S/Pconversion processing on image signals output through the third to thetenth channels CC to CJ.

In the first embodiment, address numbers of “0” to “4249” are providedand thus the number of pixels in the effective image region of the imagesensor 2231 is 4250, but the present disclosure is not limited thereto.The number of pixels in the effective image region of an image sensor inuse may be changed to any other number as appropriate.

The signal processing unit 227 generates a plurality of transmissionimage signals by executing the transmission signal generation processing(the mapping processing and the auxiliary data addition processing) onthe first to the tenth image signals FS1 to FS10 (parallel data)generated at the S/P conversion unit 226.

In the first embodiment, as illustrated in FIG. 4, the signal processingunit 227 generates four of first to fourth transmission image signalsTS1 to TS4 from the first to the tenth image signals FS1 to FS10. Thenumber of transmission image signals is not limited to four but may beany other number.

As illustrated in FIG. 4, the signal processing unit 227 includes adistribution processing unit 2271 and a data addition unit 2272.

The distribution processing unit 2271 generates four of first to fourthdistributed image signals DS1 to DS4 by distributing (executing themapping processing on) the first to the tenth image signals FS1 to FS10(parallel data) generated at the S/P conversion unit 226.

In the first embodiment, the distribution processing unit 2271distributes the first to the tenth image signals FS1 to FS10 such that,among the first to the tenth image signals FS1 to FS10, pieces of dataof MSBs of the image signals of pixels adjacent to each other areincluded in respective distributed image signals different from eachother among the first to the fourth distributed image signals DS1 toDS4. The distribution processing unit 2271 distributes the first to thetenth image signals FS1 to FS10 such that among the first to the tenthimage signals FS1 to FS10, pieces of data at the bit positions of thesecond MSBs (in the first embodiment, bit position “8”) of the imagesignals of pixels adjacent to each other are included in respectivedistributed image signals different from each other among the first tothe fourth distributed image signals DS1 to DS4. In addition, thedistribution processing unit 2271 distributes the first to the tenthimage signals FS1 to FS10 such that, among the first to the tenth imagesignals FS1 to FS10, data of the MSB of one of the image signals ofpixels adjacent to each other and data at the bit position of the secondMSB of the other image signal are included in respective distributedimage signals different from each other among the first to the fourthdistributed image signals DS1 to DS4. The distribution processing unit2271 also distributes the first to the tenth image signals FS1 to FS10such that data of the MSB of pixel data generated at each pixel and dataat the bit position of the second MSB of this pixel data are included inrespective distributed image signals different from each other among thefirst to the fourth distributed image signals DS1 to DS4.

The following describes the first to the fourth distributed imagesignals DS1 to DS4 generated at the distribution processing unit 2271with reference to the bit string of word WD illustrated in FIG. 5.

FIG. 6 is a diagram illustrating the first to the fourth distributedimage signals DS1 to DS4 generated at the distribution processing unit2271. Specifically, (a) to (d) in FIG. 6 illustrate distribution of thebit string of word WD illustrated in FIG. 5.

In (a) to (d) in FIG. 6, each bit is denoted by an address numberindicating the pixel of the corresponding pixel data, followed by a bitposition in this pixel data in parentheses.

Among the first to the tenth image signals FS1 to FS10, image signals ofpixels adjacent to each other and image signals of pixels separate fromeach other exemplarily include image signals described below.

For example, the first image signal FS1 includes pieces of pixel datagenerated at pixels of address numbers “0”, “10”, “20”, . . . . Thesecond image signal FS2 includes pieces of pixel data generated atpixels of address numbers “1”, “11”, “21”, . . . . Thus, the first andthe second image signals FS1 and FS2 are image signals of pixels(address numbers) adjacent to each other. The fifth image signal FS5includes pieces of pixel data generated at pixels of address numbers“4”, “14”, “24”, . . . . Thus, the first and the fifth image signals FS1and FS5 are image signals of pixels (address numbers) separate from eachother.

Then, as described above, the distribution processing unit 2271distributes the first to the tenth image signals FS1 to FS10 such thatpieces of data of MSBs of the image signals of pixels adjacent to eachother are included in distributed image signals different from eachother. As a result, as illustrated in (a) in FIG. 6, the firstdistributed image signal DS1 includes data of the MSB of pixel datagenerated at the pixel of address number “0” (the first image signalFS1), data of the MSB of pixel data generated at the pixel of addressnumber “4” (the fifth image signal FS5), and data of the MSB of pixeldata generated at the pixel of address number “8” (ninth image signalFS9). As illustrated in (b) in FIG. 6, the second distributed imagesignal DS2 includes data of the MSB of pixel data generated at the pixelof address number “1” (the second image signal FS2), data of the MSB ofpixel data generated at the pixel of address number “5” (the sixth imagesignal FS6), and data of the MSB of pixel data generated at the pixel ofaddress number “9” (the tenth image signal FS10). As illustrated in (c)in FIG. 6, the third distributed image signal DS3 includes data of theMSB of pixel data generated at the pixel of address number “2” (thethird image signal FS3), and data of the MSB of pixel data generated atthe pixel of address number “6” (the seventh image signal FS7). Asillustrated in (d) in FIG. 6, the fourth distributed image signal DS4includes data of the MSB of pixel data generated at the pixel of addressnumber “3” (the fourth image signal FS4), and data of the MSB of pixeldata generated at the pixel of address number “7” (the eighth imagesignal FS8).

As described above, the distribution processing unit 2271 distributesthe first to the tenth image signals FS1 to FS10 such that pieces ofdata at bit positions “8” of image signals of pixels adjacent to eachother are included in distributed image signals different from eachother, data of the MSB of one of the image signals of pixels adjacent toeach other and data at bit position “8” of the other image signal areincluded in distributed image signals different from each other, anddata of the MSB and data at bit position “8” of pixel data generated atan identical pixel are included in distributed image signals differentfrom each other. As a result, as illustrated in (a) in FIG. 6, the firstdistributed image signal DS1 includes pieces of data at bit positions“8” of pieces of pixel data (the third and the seventh image signals FS3and FS7) generated at pixels of address numbers “2” and “6” separatefrom pixels of address numbers “0”, “4”, and “8”. As illustrated in (b)in FIG. 6, the second distributed image signal DS2 includes pieces ofdata at bit positions “8” of pieces of pixel data (the fourth and eighthimage signals FS4 and FS8) generated at pixels of address numbers “3”and “7” separate from pixels of address numbers “1”, “5”, and “9”. Asillustrated in (c) in FIG. 6, the third distributed image signal DS3includes pieces of data at bit positions “8” of pieces of pixel data(the first, the fifth, and the ninth image signals FS1, FS5, and FS9)generated at pixels of address numbers “0”, “4”, and “8” separate frompixels of address numbers “2” and “6”. As illustrated in (d) in FIG. 6,the fourth distributed image signal DS4 includes pieces of data at bitpositions “8” of pieces of pixel data (the second, the sixth, and thetenth image signals FS2, FS6, and FS10) generated at pixels of addressnumbers “1”, “5”, and “9” separate from pixels of address numbers “3”and “7”.

Pieces of data at bit positions “7” to “0” may be distributed such thatthe pieces are included randomly in the first to the fourth distributedimage signals DS1 to DS4. Alternatively, the pieces may be distributedsuch that the pieces are included in a distributed image signalincluding data of bit position “8” of pixel data generated at this pixelas illustrated in FIG. 6.

In the distribution as illustrated in FIG. 6, the first and the seconddistributed image signals DS1 and DS2 each include 21 bits per word. Thethird and the fourth distributed image signals DS3 and DS4 each include29 bits per word.

In FIG. 6, the amount of data (number of bits) per word in the first tothe fourth distributed image signals DS1 to DS4 is not constant (21 bitsfor the first and the second distributed image signals DS1 and DS2, and29 bits for the third and the fourth distributed image signals DS3 andDS4), but the present disclosure is not limited thereto. The first tothe tenth image signals FS1 to FS10 may be distributed so that theamount of data is constant therebetween.

The data addition unit 2272 generates the first to the fourthtransmission image signals TS1 to TS4 by adding auxiliary data to(executing the auxiliary data addition processing on) each of the fourof the first to the fourth distributed image signals DS1 to DS4 toenable execution of the 8 bits/10 bits conversion processing at a laterstage.

In the first embodiment, the data addition unit 2272 adds auxiliary dataof 11 bits per word to each of the first and the second distributedimage signals DS1 and DS2 (21 bits). The data addition unit 2272 addsauxiliary data of 3 bits per word to each of the third and the fourthdistributed image signals DS3 and DS4 (29 bits).

The auxiliary data added to the first to the fourth distributed imagesignals DS1 to DS4 may be any data that allows execution of the 8bits/10 bits conversion processing at a later stage.

The drivers 228 are provided in accordance with the number oftransmission image signals generated at the signal processing unit 227.Specifically, in the first embodiment, as illustrated in FIG. 4, thefour drivers 228 of first to fourth drivers 2281 to 2284 are provided.The four of the first to the fourth drivers 2281 to 2284 execute theencoding processing (in the first embodiment, the 8 bits/10 bitsconversion processing) on the first to the fourth transmission imagesignals TS1 to TS4 generated at the signal processing unit 227. The fourof the first to the fourth drivers 2281 to 2284 execute the P/Sconversion processing on the first to the fourth transmission imagesignals TS1 to TS4 after the encoding processing to convert the signalsinto serial data. Although not specifically illustrated, a clock signalis superimposed on this serial data, and, for example, a K codeindicating the start position and the end position of effective data isinserted into the serial data.

The transmission signal processing unit 224 described above is achievedby a programmable logic device such as a field-programmable gate array(FPGA).

The electrical-optical conversion unit 225 converts the first to thefourth transmission image signals TS1 to TS4 (serial data) output fromthe transmission signal processing unit 224 (the four of the first tothe fourth drivers 2281 to 2284) into optical signals, and outputs theoptical signals to the first transmission cable 23 (the first to thefourth optical fibers 2321 to 2324). Then, the first to the fourthoptical fibers 2321 to 2324 transmit the first to the fourthtransmission image signals TS1 to TS4 to the control device 6.

Configuration of Control Device

The following describes the configuration of the control device 6 withreference to FIG. 2.

As illustrated in FIG. 2, the control device 6 includes anoptical-electrical conversion unit 61, a received signal processing unit62, an image processing unit 63, a display control unit 64, a controlunit 65, an input unit 66, an output unit 67, and a storage unit 68.

The optical-electrical conversion unit 61 converts the four opticalsignals (the four of the first to the fourth transmission image signalsTS1 to TS4) received through the first to the fourth optical fibers 2321to 2324 into electric signals (serial data).

FIG. 7 is a block diagram of the configuration of the received signalprocessing unit 62.

The received signal processing unit 62 functions as a medical controldevice according to the present disclosure and executes, on the fourpieces of serial data (the four of the first to the fourth transmissionimage signals TS1 to TS4) output from the optical-electrical conversionunit 61, various kinds of processing such as transmission failuredetection processing, the S/P conversion processing, decoding processing(M bit/N (<M) bit conversion processing (in the first embodiment, 10bits/8 bits conversion processing)), mapping decoding processing, andthe P/S conversion processing. As illustrated in FIG. 7, the receivedsignal processing unit 62 includes a plurality of signal detection units621, a transmission failure detection unit 622, and a signal restoringunit 623.

The signal detection units 621 are provided in accordance with thenumber of optical fibers 232 (the first to the fourth transmission imagesignals TS1 to TS4) included in the first transmission cable 23.Specifically, in the first embodiment, the four signal detection units621 are provided. Hereinafter, the signal detection units 621corresponding to the first to the fourth transmission image signals TS1to TS4 are referred to as first to fourth signal detection units 6211 to6214, respectively (FIG. 7). The first to the fourth signal detectionunits 6211 to 6214 have an identical configuration, and thus only theconfiguration of the first signal detection unit 6211 corresponding tothe first transmission image signal TS1 will be described below. For thepurpose of description, FIG. 7 only illustrates a specific configurationof the first signal detection unit 6211, whereas specific configurationsof the second to the fourth signal detection units 6212 to 6214 areomitted in the illustration.

As illustrated in FIG. 7, the first signal detection unit 6211 includesa clock recovery (CDR) unit 624, an S/P conversion unit 625, a K codedetection unit 626, and a decoding unit 627.

The CDR unit 624 executes CDR processing that recovers the superimposedclock signal from the first transmission image signal TS1 (serial data)input to the optical-electrical conversion unit 61 through the opticalfiber 232 (first optical fiber 2321) and converted at theoptical-electrical conversion unit 61. Then, when the execution of theCDR processing is successful (the recovery of the superimposed clocksignal is successful), the CDR unit 624 outputs processing executioninformation indicating the successful execution to the transmissionfailure detection unit 622. When the execution of the CDR processing isfailed, the CDR unit 624 outputs, to the transmission failure detectionunit 622, failed execution information indicating the failure, andidentification information for identifying the optical fiber 232 (firstoptical fiber 2321) corresponding to the CDR unit 624.

The S/P conversion unit 625 executes the S/P conversion processing onthe first transmission image signal TS1 (serial data) after the CDRprocessing to convert the signal into parallel data.

The K code detection unit 626 detects the K code from the firsttransmission image signal TS1 (parallel data) after the S/P conversionprocessing at the S/P conversion unit 625 to perform timing detection ofdata, and executes K code detection processing that acquires theeffective data from the first transmission image signal TS1 (paralleldata). Then, when the execution of the K code detection processing issuccessful (the acquisition of the effective data is successful), the Kcode detection unit 626 outputs processing execution informationindicating the successful execution to the transmission failuredetection unit 622. When the execution of the K code detectionprocessing is failed, the K code detection unit 626 outputs, to thetransmission failure detection unit 622, failed execution informationindicating the failure, and identification information for identifyingthe optical fiber 232 (first optical fiber 2321) corresponding to the Kcode detection unit 626.

In the first embodiment, the K code detection unit 626 is employed, butthe present disclosure is not limited thereto. When information otherthan the K code is inserted into the first to the fourth transmissionimage signals TS1 to TS4 by the camera head 22, a component having afunction of detecting this information (component that outputs, to thetransmission failure detection unit 622, for example, whether thisinformation may be detected) may be employed.

The decoding unit 627 executes the decoding processing (in the firstembodiment, 10 bits/8 bits conversion processing) on the firsttransmission image signal TS1 (effective data (parallel data) acquiredat the K code detection unit 626) after the K code detection processingat the K code detection unit 626.

The transmission failure detection unit 622 detects any failure oftransmission of optical signals through the first to the fourth opticalfibers 2321 to 2324 based on the information output from the first tothe fourth signal detection units 6211 to 6214 (the CDR unit 624 and theK code detection unit 626), and specifies an optical fiber in which atransmission failure has occurred.

Specifically, the first to the fourth signal detection units 6211 to6214 and the transmission failure detection unit 622 execute thetransmission failure detection processing to detect any failure oftransmission of optical signals through the first to the fourth opticalfibers 2321 to 2324, and specifies an optical fiber in which thetransmission failure has occurred.

Then, the transmission failure detection unit 622 outputs transmissionfailure information (information indicating whether a transmissionfailure has occurred, and when a transmission failure occurs, an opticalfiber in which this transmission failure has occurred) to the controlunit 65.

The signal restoring unit 623 restores image signals (the first to thetenth image signals FS1 to FS10 (parallel data)) before the mappingprocessing at the camera head 22 by executing the mapping decodingprocessing on the first to the fourth transmission image signals TS1 toTS4 (parallel data) after the decoding processing at the decoding units627 in the first to the fourth signal detection units 6211 to 6214.

Specifically, the signal restoring unit 623 extracts the first to thefourth distributed image signals DS1 to DS4 from the first to the fourthtransmission image signals TS1 to TS4 after the decoding processing atthe decoding units 627 in the first to the fourth signal detection units6211 to 6214, respectively. Then, the signal restoring unit 623 restoresimage signals (the first to the tenth image signals FS1 to FS10) beforethe mapping processing at the camera head 22 by executing the inverseprocessing (mapping decoding processing) of the mapping processing atthe camera head 22 on these extracted first to fourth distributed imagesignals DS1 to DS4.

Similarly to the transmission signal processing unit 224, the receivedsignal processing unit 62 described above is achieved by a programmablelogic device such as an FPGA.

The image processing unit 63 executes, on an image signal (serial data)restored at the received signal processing unit 62, various kinds ofimage processing such as development processing (demosaic processing),noise reduction, color correction, color enhancement, and outlineenhancement.

The display control unit 64 generates a display image signal from theimage signal (serial data) after the various kinds of image processingat the image processing unit 63, and outputs the display image signal tothe display device 4 through the second transmission cable 5. Then, thedisplay device 4 displays an image (hereinafter referred to as anobservation image) based on this display image signal. When atransmission failure is detected by the transmission failure detectionunit 622, the display control unit 64 generates an image signal fordisplaying, on the display device 4, a superimposed image obtained bysuperimposing, on the observation image, a message indicating theoccurrence of the transmission failure and a message indicating anoptical fiber in which the transmission failure has occurred, andoutputs the image signal to the display device 4 through the secondtransmission cable 5. Then, the display device 4 displays thesuperimposed image (image in which the messages are superimposed on theobservation image) based on this image signal.

In other words, the display device 4 functions as a notification unitaccording to the present disclosure. The display control unit 64functions as a notification control unit according to the presentdisclosure.

The control unit 65 includes, for example, a CPU, and controls operationof the light source device 3, the drive unit 222, the imaging unit 223,and the transmission signal processing unit 224, and operation of theentire control device 6 by outputting a control signal through the thirdtransmission cable 7 and the electric wires 231.

The input unit 66 includes, for example, an operation device such as amouse, a keyboard, or a touch panel to receive an operation by a user.

The output unit 67 includes, for example, a speaker or a printer tooutput various kinds of information. When a transmission failure isdetected by the transmission failure detection unit 622, the output unit67 outputs sound indicating the occurrence of the transmission failure,and sound indicating an optical fiber in which this transmission failurehas occurred.

In other words, the output unit 67 functions as the notification unitaccording to the present disclosure. The control unit 65 functions asthe notification control unit according to the present disclosure.

The notification unit according to the present disclosure is not limitedto the display device 4 and the output unit 67, but may be, for example,an LED that gives notification of predetermined information by lightingor flashing.

The medical observation system 1 according to the first embodimentdescribed above achieves an effect described below.

FIGS. 8A, 8B, and FIG. 9 are each a diagram illustrating the effect ofthe first embodiment of the present disclosure. Specifically, FIG. 8A isa diagram illustrating an observation image FG1 displayed on the displaydevice 4 when a transmission failure occurs in any of the first and thethird optical fibers 2321 and 2323. FIG. 8B is a diagram illustrating anobservation image FG2 displayed on the display device 4 when atransmission failure occurs in any of the second and the fourth opticalfibers 2322 and 2324. FIG. 9 is a diagram illustrating the amount ofdata at each bit position of 10-bit pixel data.

In FIGS. 8A and 8B, for the purpose of illustration, the address number(FIG. 3A) corresponding to each pixel at the image sensor 2231 isattached to part of the observation images FG1 and FG2.

Specifically, in 10-bit pixel data, as illustrated in FIG. 9, the amountof data of the MSB accounts for half of the amount of the entire pixeldata. The amount of data at bit position “8” accounts for a quarter ofthe amount of the entire pixel data. In other words, data at the bitposition of a more significant digit is important data in pixel data.

In the medical observation system 1 according to the first embodiment,the first to the tenth image signals FS1 to FS10 are distributed intothe first to the fourth distributed image signals DS1 to DS4 such that,among the first to the tenth image signals FS1 to FS10, pieces of dataof MSBs of the image signals of pixels adjacent to each other areincluded in respective distributed image signals different from eachother among the first to the fourth distributed image signals DS1 toDS4. In the medical observation system 1, the first to the tenth imagesignals FS1 to FS10 are distributed into the first to the fourthdistributed image signals DS1 to DS4 such that, among the first to thetenth image signals FS1 to FS10, pieces of data at bit positions “8”,which are the second MSBs, of the image signals of pixels adjacent toeach other are included in respective distributed image signalsdifferent from each other among the first to the fourth distributedimage signals DS1 to DS4. In the medical observation system 1, the firstto the tenth image signals FS1 to FS10 are distributed into the first tothe fourth distributed image signals DS1 to DS4 such that, among thefirst to the tenth image signals FS1 to FS10, data of the MSB of one ofthe image signals of pixels adjacent to each other and data at bitposition “8” of the other image signal are included in respectivedistributed image signals different from each other among the first tothe fourth distributed image signals DS1 to DS4. In the medicalobservation system 1, the first to the tenth image signals FS1 to FS10are distributed into the first to the fourth distributed image signalsDS1 to DS4 such that data of the MSB of pixel data generated at eachpixel and data at bit position “8” of the pixel data are included inrespective distributed image signals different from each other among thefirst to the fourth distributed image signals DS1 to DS4.

As a result, the first distributed image signal DS1 includes data of theMSBs of the first image signal FS1 including pieces of pixel datagenerated at pixels of address numbers “0”, “10”, “20”, . . . , thefifth image signal FS5 including pieces of pixel data generated atpixels of address numbers “4”, “14”, “24”, . . . , and the ninth imagesignal FS9 including pieces of pixel data generated at pixels of addressnumbers “8”, “18”, “28”, . . . , and pieces of data at bit positions “8”of the third image signal FS3 including pieces of pixel data generatedat pixels of address numbers “2”, “12”, “22”, . . . , and the seventhimage signal FS7 including pieces of pixel data generated at pixels ofaddress numbers “6”, “16”, “26”,

Thus, when a transmission failure occurs in the first optical fiber2321, as illustrated in FIG. 8A, in the observation image FG1 displayedon the display device 4, the luminance value is reduced on verticallines (hatched lines in FIG. 8A) of the first column, the third column,the fifth column, the seventh column, the ninth column, . . .corresponding to the first, the third, the fifth, the seventh, and theninth image signals FS1, FS3, FS4, FS7, and FS9 along with a loss of thefirst distributed image signal DS1. The same description applies to acase in which a transmission failure has occurred in the third opticalfiber 2323 (the third distributed image signal DS3 is lost).

The second distributed image signal DS2 includes data of the MSBs of thesecond image signal FS2 including pieces of pixel data generated atpixels of address numbers “1”, “11”, “21”, . . . , the sixth imagesignal FS6 including pieces of pixel data generated at pixels of addressnumbers “5”, “15”, “25”, . . . , and the tenth image signal FS10including pieces of pixel data generated at pixels of address numbers“9”, “19”, “29”, . . . , and pieces of data at bit positions “8” of thefourth image signal FS4 including pieces of pixel data generated atpixels of address numbers “3”, “13”, “23”, . . . , and the eighth imagesignal FS8 including pieces of pixel data generated at pixels of addressnumbers “7”, “17”, “27”, . . . .

Thus, when a transmission failure occurs in the second optical fiber2322, as illustrated in FIG. 8B, in the observation image FG2 displayedon the display device 4, the luminance value is reduced on verticallines (hatched lines in FIG. 8B) of the second column, the fourthcolumn, the sixth column, the eighth column, and the tenth column, . . .corresponding to the second, the fourth, the sixth, the eighth, and thetenth image signals FS2, FS4, and FS6, FS8, and FS10 along with a lossof the second distributed image signal DS2. The same description appliesto a case in which a transmission failure occurs (the fourth distributedimage signal DS4 is lost) in the fourth optical fiber 2324.

In other words, the first to the tenth image signals FS1 to FS10 aredistributed such that data of the MSB and data at bit position “8” ofpixel data generated at an identical pixel are included in distributedimage signals different from each other. With this configuration, when atransmission failure occurs in any of the first to the fourth opticalfibers 2321 to 2324 and data of one of the MSB and bit position “8” ofeach pixel data included in a distributed image signal corresponding tothe optical fiber in which this transmission failure has occurred islost, the loss may be compensated with data of the other of the MSB andbit position “8” of each pixel data included in a distributed imagesignal transmitted through an optical fiber in which no transmissionfailure has occurred. In other words, a transmission failure in any ofthe first to the fourth optical fibers 2321 to 2324 only causes thereduction in the luminance value but not losses of images at pixels onthe hatched vertical lines in FIGS. 8A and 8B.

In addition, the first to the tenth image signals FS1 to FS10 aredistributed such that, among the first to the tenth image signals FS1 toFS10, pieces of data of MSBs of the image signals of pixels adjacent toeach other are included in distributed image signals different from eachother, pieces of data at bit positions “8” of these image signals areincluded in distributed image signals different from each other, anddata of the MSB of one of these image signals and data of bit position“8” of the other image signal are included in distributed image signalsdifferent from each other. With this configuration, as illustrated inFIG. 8A or 8B, when a transmission failure occurs in any of the first tothe fourth optical fibers 2321 to 2324, any reduction of the luminancevalue occurs on vertical lines separate from each other, not on verticallines adjacent to each other. The observation images FG1 and FG2 inwhich the luminance value is reduced on vertical lines separate fromeach other allow easier entire recognition thereof than an observationimage in which the luminance value is reduced on vertical lines adjacentto each other.

Thus, the observation images FG1 and FG2 suitable for observation may bedisplayed when a transmission failure occurs in any of the first to thefourth optical fibers 2321 to 2324.

At least two signal transmission paths through which an identical imagesignal is transmitted are not included in the medical observation system1 according to the first embodiment, thereby achieving a simplifiedstructure without a redundant signal transmission path that isunnecessary when no transmission failure occurs.

In the medical observation system 1 according to the first embodiment,when a transmission failure is detected, notification of predeterminedinformation (information indicating the occurrence of the transmissionfailure and an optical fiber in which the transmission failure hasoccurred) is given through the display device 4 and the output unit 67.

This configuration allows a user such as a doctor to recognize theoccurrence of the transmission failure in any of the first to the fourthoptical fibers 2321 to 2324. This may also suggest, to this user,replacement of the optical fiber in which the transmission failure hasoccurred.

In the first embodiment described above, the electrical-opticalconversion unit 225 is provided to the camera head 22, but the presentdisclosure is not limited thereto. For example, the electrical-opticalconversion unit 225 may be provided to the first transmission cable 23including the connector CN2. Moreover, at least part or all of theinternal configuration (function) of the transmission signal processingunit 224 as the medical signal processing device according to thepresent disclosure may be provided to the first transmission cable 23including the connector CN2. In this case, an electric signal is outputfrom the camera head 22, converted into an optical signal at theelectrical-optical conversion unit 225 provided to the firsttransmission cable 23, and transmitted as a transmission image signalthrough the optical fibers 232 (signal transmission paths).

Second Embodiment

The following describes a second embodiment of the present disclosure.

In the following description, any component identical to that in thefirst embodiment described above is denoted by an identical referencesign, and detailed description thereof will be omitted or simplified.

In the medical observation system 1 according to the first embodimentdescribed above, the present disclosure is applied to the endoscope 2including the camera head 22.

In a medical observation system according to the second embodiment,however, the present disclosure is applied to what is called a videoscope including an imaging unit at a leading end of an insertion unit ofan endoscope.

FIG. 10 is a diagram illustrating a schematic configuration of a medicalobservation system 1A according to the second embodiment of the presentdisclosure.

As illustrated in FIG. 10, the medical observation system 1A accordingto the second embodiment includes an endoscope 2A configured to generatean image signal by capturing the inside of the body image at anobservation site through an insertion unit 21A inserted into the insideof a living body and generate a plurality of transmission image signalsfrom this image signal, the light source device 3 configured to generateillumination light to be emitted from a leading end of the endoscope 2A,the control device 6 configured to receive the transmission imagesignals generated at the endoscope 2A and process the transmission imagesignals, and the display device 4 connected with the control device 6through the second transmission cable 5 and configured to display animage based on the image signals processed at the control device 6.

As illustrated in FIG. 10, the endoscope 2A includes the flexibleelongated insertion unit 21A, an operation unit 22A connected with abase end side of the insertion unit 21A and configured to receiveinputting of various operation signals, and a universal code 23Aextending from the operation unit 22A in a direction different from adirection in which the insertion unit 21A extends and including variousbuilt-in cables connected with the light source device 3 and the controldevice 6.

As illustrated in FIG. 10, the insertion unit 21A includes a leading endpart 211 including a built-in imaging unit (not illustrated) configuredto generates an image signal by capturing an image of the inside of theliving body, a bent part 212 that includes a plurality of bent piecesand may be freely bent, and an elongated flexible tube 213 connectedwith a base end side of the bent part 212.

Although not illustrated in detail, built-in components similar to thetransmission signal processing unit 224 and the electrical-opticalconversion unit 225 described in the first embodiment above are includedinside the operation unit 22A. The image signal generated at the imagingunit described above is processed at this transmission signal processingunit. The universal code 23A has a configuration substantially same asthe first transmission cable 23 described in the first embodiment above.Then, a plurality of transmission image signals (optical signals)processed (generated) inside the operation unit 22A (the transmissionsignal processing unit and the electrical-optical conversion unit) areoutput to the control device 6 through the universal code 23A.

When a soft endoscope (the endoscope 2A) is used as in the secondembodiment described above, the same effect as that of the firstembodiment described above is achieved.

Third Embodiment

The following describes a third embodiment of the present disclosure.

In the following description, any component identical to that in thefirst embodiment described above is denoted by an identical referencesign, and detailed description thereof will be omitted or simplified.

In the medical observation system 1 according to the first embodimentdescribed above, the present disclosure is applied to the endoscope 2including the camera head 22.

In a medical observation system according to the third embodiment,however, the present disclosure is applied to a surgical microscopeconfigured to capture an enlarged image of a predetermined viewingregion in the inside of a subject (the inside of a living body) or onthe surface of the subject (the surface of the living body).

FIG. 11 is a diagram illustrating a schematic configuration of a medicalobservation system 1B according to the third embodiment of the presentdisclosure.

As illustrated in FIG. 28, the medical observation system 1B accordingto the sixth embodiment includes a surgical microscope 2B configured togenerate an image signal by capturing an image for observing an objectand generate a plurality of transmission image signals from this imagesignal, the control device 6 configured to receive the transmissionimage signals generated at the surgical microscope 2B and process thesetransmission image signals, and the display device 4 connected with thecontrol device 6 through the second transmission cable 5 and configuredto display an image based on the image signals processed at the controldevice 6.

As illustrated in FIG. 11, the surgical microscope 2B includes amicroscope unit 22B configured to generate an image signal by capturingan enlarged image of a small site of the object and generate a pluralityof transmission image signals from this image signal, a support unit 24connected with a base end part of the microscope unit 22B and includingan arm rotatably supporting the microscope unit 22B, and a base unit 25rotatably holding a base end part of the support unit 24 and movable ona floor surface.

As illustrated in FIG. 11, the control device 6 is installed in the baseunit 25.

Instead of being provide movable on the floor surface, the base unit 25may be fixed on, for example, a ceiling or a wall surface to support thesupport unit 24. The base unit 25 may include a light source unitconfigured to generate illumination light to be emitted to the objectfrom the surgical microscope 2B.

Although not illustrated in detail specific, the microscope unit 22Bincludes an imaging unit configured to generate an image signal bycapturing an image of the inside of the living body, and built-incomponents similar to the transmission signal processing unit 224 andthe electrical-optical conversion unit 225 described in the firstembodiment above. The image signal generated at the imaging unit isprocessed at the transmission signal processing unit. Then, a pluralityof transmission image signals (optical signals) processed (generated) atthe microscope unit 22B (the transmission signal processing unit and theelectrical-optical conversion unit) are output to the control device 6through the first transmission cable 23 wired along the support unit 24.

When the surgical microscope 2B is used as in the third embodimentdescribed above, the same effect as that of the first embodimentdescribed above is achieved.

Other Embodiments

The configurations to achieve the present disclosure are describedabove, but the present disclosure is not limited to the first to thethird embodiments described above.

In the first to the third embodiments described above, a plurality oftransmission image signals are transmitted as optical signals from thecamera head 22, the operation unit 22A, and the microscope unit 22A tothe control device 6, but the present disclosure is not limited thereto.The transmission image signals may be transmitted as electric signals.In other words, the optical fibers 232 as signal transmission pathsaccording to the present disclosure included in the first transmissioncable 23 and the universal code 23A may be replaced with electric wires.In this case, the electrical-optical conversion unit 225 and theoptical-electrical conversion unit 61 are omitted.

In the transmission signal processing unit 224 according to the first tothe third embodiments described above, the auxiliary data additionprocessing is executed after the mapping processing, but the presentdisclosure is not limited thereto. The mapping processing may beexecuted after the auxiliary data addition processing (in whichauxiliary data is added to the first to the tenth image signals FS1 toFS10, and the first to the fourth transmission image signals TS1 to TS4are generated by distributing the first to the tenth image signals FS1to FS10 to which this auxiliary data is added).

In the first to the third embodiments described above, the scheme ofdistribution of the first to the tenth image signals FS1 to FS10 togenerate the first to the fourth distributed image signals DS1 to DS4 isnot limited to the distribution schemes described in the first to thethird embodiments above. Any other distribution scheme may be employedas long as, among the first to the tenth image signals FS1 to FS10,pieces of data of MSBs of the image signals of pixels adjacent to eachother are included in distributed image signals different from eachother through the scheme.

A medical signal processing device according to the present disclosuregenerates a plurality of distributed image signals by distributing aplurality of pixel data groups received by the medical signal processingdevice in parallel such that, among the pixel data groups, pieces ofdata at the bit positions of the most significant digits of the pixeldata groups of pixels adjacent to each other are included in therespective distributed image signals different from each other. Then,the distributed image signals are transmitted to an external medicalcontrol device through a plurality of respective signal transmissionpaths.

A transmission failure that has occurred in any of the signaltransmission paths results in a loss of a distributed image signalcorresponding to the signal transmission path in which this transmissionfailure has occurred. The distributed image signals generated at themedical signal processing device according to the present disclosureinclude one of pieces of data at the bit positions of the mostsignificant digits of the pixel data groups of pixels adjacent to eachother, but do not include the other piece of data. In pixel data, theamount of data at the bit position of the most significant digit islarger than the amount of data at any other bit position, and thus thedata at the bit position of the most significant digit is extremelyimportant.

With this configuration, unlike a configuration in which a plurality ofdistributed image signals are generated by distributing a plurality ofpixel data groups such that pieces of data at the bit positions of themost significant digits of the pixel data groups of pixels adjacent toeach other are included in an identical distributed image signal, anyloss of data at the bit position of the most significant digit occurs atpixels separate from each other, not at pixels adjacent to each other,when a transmission failure occurs in any of the signal transmissionpaths. An image in which a loss of data at the bit position of the mostsignificant digit occurs at pixels separate from each other allowseasier entire recognition thereof than an image in which a loss of dataat the bit position of the most significant digit occurs at pixelsadjacent to each other.

With this configuration, an image suitable for observation may becontinuously displayed when a transmission failure occurs in a signaltransmission path. In addition, a simplified structure without aredundant signal transmission path that is unnecessary when notransmission failure occurs may be achieved because the distributedimage signals different from each other are transmitted to the externalmedical control device through the respective signal transmission paths.

A medical observation system according to the present disclosureincludes the medical signal processing device and the medical controldevice described above, and thus provides an effect similar to theabove-described effect of the medical signal processing device.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A medical signal processing device, comprising:processing circuitry including hardware and configured to receive animage signal, wherein the image signal includes a plurality of pixeldata groups of respective pixels arrayed at a constant interval amongpixels sequentially arrayed in a predetermined direction in an imagemade of pixels arrayed in a matrix, wherein the pixel data groups aredata of respective pixels different from each other, and wherein thepixel data groups are received in parallel, generate a plurality ofdistributed image signals by distributing the pixel data groups,distribute the pixel data groups such that, among the pixel data groups,pieces of data at bit positions of most significant digits of the pixeldata groups of pixels adjacent to each other are included in therespective distributed image signals different from each other, andcontrol transmission of the distributed image signals to an externalmedical control device through a plurality of respective signaltransmission paths.
 2. The medical signal processing device according toclaim 1, wherein the processing circuitry is further configured todistribute the pixel data groups such that, among the pixel data groups,pieces of data at bit positions of second most significant digits of thepixel data groups of pixels adjacent to each other are included in therespective distributed image signals different from each other.
 3. Themedical signal processing device according to claim 1, wherein theprocessing circuitry is further configured to distribute the pixel datagroups such that, among the pixel data groups, data at a bit position ofa most significant digit of one of the pixel data groups of pixelsadjacent to each other and data at a bit position of a second mostsignificant digit of the other pixel data group are included in therespective distributed image signals different from each other.
 4. Themedical signal processing device according to claim 1, wherein theprocessing circuitry is further configured to distribute the pixel datagroups such that data at a bit position of a most significant digit ofpixel data of each pixel and data at a bit position of a second mostsignificant digit of the pixel data are included in the distributedimage signals different from each other.
 5. A medical observation systemcomprising: a medical signal processing device including processingcircuitry including hardware and configured to receive an image signal,wherein the image signal includes a plurality of pixel data groups ofrespective pixels arrayed at a constant interval among pixelssequentially arrayed in a predetermined direction in an image made ofpixels arrayed in a matrix, wherein the pixel data groups are data ofrespective pixels different from each other, and wherein the pixel datagroups are received in parallel, to generate a plurality of distributedimage signals by distributing the pixel data groups, to distribute thepixel data groups such that, among the pixel data groups, pieces of dataat bit positions of most significant digits of the pixel data groups ofpixels adjacent to each other are included in the respective distributedimage signals different from each other, and control transmission of thedistributed image signals to an external medical control device througha plurality of respective signal transmission paths; a plurality ofsignal transmission paths through which the respective distributed imagesignals transmitted from the medical signal processing device aretransmitted; and a medical control device including second processingcircuitry including hardware and configured to receive the distributedimage signals through the signal transmission paths and restore theimage signal based on the distributed image signals.
 6. The medicalobservation system according to claim 5, wherein the second processingcircuitry is further configured to detect a signal transmission failurein the signal transmission paths, give notification of predeterminedinformation, and give notification of the predetermined information whena transmission failure is detected.
 7. The medical observation systemaccording to claim 5, wherein the signal transmission paths each includea light transmission path through which an optical signal istransmitted, and the medical observation system includes: anelectrical-optical conversion circuitry configured to convert aplurality of electric signals based on the distributed image signalsinto a plurality of respective optical signals, and output the opticalsignals to the respective signal transmission paths, and anoptical-electrical conversion circuitry configured to convert theoptical signals received through the signal transmission paths into aplurality of respective electric signals, and output the electricsignals to the medical control device.